1. Technical Field
The present invention relates to a robot, a robot control device, and a robot system.
2. Related Art
JP-A-2011-136395 discloses a robot including a six-axis sensor that is installed to a sixth link at a front end portion, that is, the front-most end side of the robot. The six-axis sensor detects accelerations in the directions of an X-axis, a Y-axis, and a Z-axis perpendicular to one another and accelerations about the X-axis, the Y-axis, and the Z-axis. Based on the detection results of the six-axis sensor, a vibration component of the angular velocity of each link about a desired axis is obtained, and control for suppressing the vibration is performed. The vibration component of the angular velocity of the link is referred to as “torsional angular velocity”, “vibration angular velocity”, or the like.
In the robot disclosed in JP-A-2011-136395, since the posture of the six-axis sensor is changed due to the motion of the robot, it is necessary to perform coordinate axis transformation or the like, called Jacobi's transformation, to obtain the vibration component of the angular velocity of each link from the detection results of the six-axis sensor. Furthermore, it is necessary to make a calculation according to the rotation angle of a motor changing every moment.
Because of this, complex and massive arithmetic processing is needed, and a control device having a high-performance and expensive CPU (Central Processing Unit) or the like is needed, leading to a problem of increased cost.
Moreover, since complex and massive arithmetic processing is needed, an arithmetic error is likely to occur and thus the arithmetic error causes a problem of failing to sufficiently suppress vibration.